The present invention relates to a brake pedal apparatus for a vehicle such as an automotive vehicle.
In recent years, various improvement work has been undertaken to provide a brake system for a vehicle, more specifically, a brake pedal apparatus for a vehicle such as an automotive vehicle, one typical example of which is disclosed in Japanese Utility Model Application Laid-Open Publication No. H6-1113. In such a brake pedal apparatus, a pedal bracket, which pivotally supports an upper portion of a pedal arm, is fixedly connected to a dash floor panel and a lower portion of a dash upper panel connected to the dash floor panel and protruding into a vehicle compartment, with depression of the pedal arm allowing a push rod, which is connected to an upper portion of the pedal arm, to move forward to render a master vac. of the brake system operative.
In such a structure of the brake pedal apparatus, in the event that the master vac. having a master cylinder and the dash floor panel, to which the master vac. is fixed, are moved and deformed rearward of the vehicle during a frontal collision of the vehicle, the pedal arm encounters a movement in a direction opposite to a depressing direction of the pedal arm through the push rod of the master vac., with a depressible position of the brake pedal being dislocated from its usual position to an undesired uncomfortable position to provide a differential feeling touch to a driver in the vehicle.
The present invention has been made in view of the above-described studies by the present inventor and has an object to provide a brake pedal apparatus for a vehicle wherein a pedal arm is effectively prevented from being subjected to impact load through a push rod of a master vac. during a frontal collision of the vehicle for thereby effectively avoiding a differential feeling touch to be given to a driver of the vehicle.
According to one aspect of the present invention, there is provided a brake pedal apparatus for a vehicle provided with a dash panel and a body structural member located upwardly rearward of the dash panel in the vehicle. The brake pedal apparatus includes: a pedal bracket having a side wall connected to the dash panel, an upper wall connected to an upper end of the side wall, and a pivot shaft mounted to the side wall, the upper wall being attached to the body structural member; a pivot bracket pivotally supported on the pivot shaft and having a pedal shaft located forward of the pivot shaft in the vehicle; a pedal arm pivotally supported on the pedal shaft; a slide plate attached to the body structural member and located between the body structural member and the pedal bracket, the pivot bracket being normally held in engagement with the slide plate; an impact absorbing section permitting relative movement of the pivot bracket and the body structural member in a longitudinal direction of the vehicle when the pedal bracket encounters an external force directed rearward of the vehicle at a level beyond a predetermined load, in such a manner that the pivot bracket disengages from the slide plate to allow the pivot bracket to rotate about the pivot shaft while rotating the pedal shaft therewith rearwardly downward of the vehicle; and a rotational motion assisting section formed on the pivot bracket and normally held in an inoperative position, the rotational motion assisting section being operable to be brought into abutting engagement with at least one of the body structural member and the slide plate to promote rotational movement of the pivot bracket about the pivot shaft caused by the impact absorbing section.
In other words, with respect to the present invention, a brake pedal apparatus for a vehicle includes: a pedal bracket having a side wall connected to the dash panel, an upper wall connected to an upper end of the side wall, and a pivot shaft mounted to the side wall, the upper wall being attached to the body structural member; a pivot bracket pivotally supported on the pivot shaft and having a pedal shaft located forward of the pivot shaft in the vehicle; a pedal arm pivotally supported on the pedal shaft; a slide plate attached to the body structural member and located between the body structural member and the pedal bracket, the pivot bracket being normally held in engagement with the slide plate; permitting means for permitting relative movement of the pivot bracket and the body structural member in a longitudinal direction of the vehicle when the pedal bracket encounters an external force directed rearward of the vehicle at a level beyond a predetermined load, in such a manner that the pivot bracket disengages from the slide plate to allow the pivot bracket to rotate about the pivot shaft while rotating the pedal shaft therewith rearwardly downward of the vehicle; and promoting means for promoting rotational movement of the pivot bracket about the pivot shaft caused by the permitting means when the promoting means is operable to be brought into abutting engagement with at least one of the body structural member and the slide plate.
Other and further features, advantages, and benefits of the present invention will become more apparent from the following description taken in conjunction with the following drawings.